Any occurrence of Noseybonk, a little-known source of Nightmare Fuel from the old British 80s Game ShowJigsaw. Yeah, an already unnerving entity gets made even more terrifying.
Even better, Ashen's Noseybonk mask is scarier than the original!
In his review of Girl's Toys, he brought up a doll dressed up in wedding garb. This wouldn't be so bad if not for the positioning of the doll's eyes inducing this trope with a very big bang.
The Creme Egg knockoffs in the Easter Tat Special were disgusting and rancid, but not initially horrifying. And then Ashen finds a maggot in the middle of a candy piece.
Though admittedly a fake one, planted as part of a behind the scenes prank.
What he actually did is known as Circuit-Bending. Basically he cut off the outer coating (skinned it alive) then fiddled with the internal circuits. The result made it sound like E.T was being brutally murdered while his screams were muffled. This combined with Ashen's speech about how he is going to make it better causes it to be nightmare fuel. Now, imagine E.T was sentient...